מחט או טבעת

A [metal] needle or a ring [that were a progenitor of tumah]

that were found in (an indentation) the floor of a tanur, (the floor of a tanur was the ground, and in this case the needle or ring were there prior to the tanur being placed above them)

[and they were] visible but did not extend [into the airspace of the tanur]

if one bakes dough

and it touches them [the needle or ring]

it [the tanur] is tamei (as if the dough touches them while baking, they and the depression that they lie in are considered to have been in the airspace of the oven).

By what dough was this said?

With intermediate dough (not so soft as to very easily sink into the depression in the floor where the needle or ring lie, nor so thick as to not sink at all).

If they [a tahor ring or needle] were found in the coating of the tanur (the coating was the thick exterior layer of clay that covered the interior earthenware vessel of a tanur)

[and tanur was under the same canopy as a cadaver, and the opening at its top was] sealed with a tightly fitting cover (thus preventing it from becoming tamei),

if in a tamei [tanur] they are tamei (if the tanur had become tamei prior to its sharing a roof with the cadaver, it loses its ability to protect from the tumah of the cadaver).

and if in a tahor [tanur] they are tahor.

If they are found in the stopper of a barrel (made of earthenware, these stoppers were mushroom-shaped, wider at their top, and narrow below where it had to fit into the opening of the barrel)

from its sides (i.e. they were in the wide part of the stopper that did not actually sit directly above the mouth of the barrel) they are tamei,

from opposite its mouth they are tahor (as this part of the stopper is deemed a necessary component of the barrel);

if they are visible in it (i.e. the needle or ring, while embedded in the stopper, can be seen from inside the barrel

but are not in its airspace

they are tahor (if they had extended into the airspace of the barrel, they would no longer be considered an integral part of the stopper, and so would lose the protection of the barrel; by rabbinical decree, the protection afforded by earthenware vessels only extended to the vessels and food and beverages therein, but not to items that can be purified by immersion, such as these metal implements);

if they are sunken into it [into the stopper]

and beneath them is like the peel of garlic (i.e. the material of the stopper that lies between them and the airspace of the barrel is as thin as a garlic peel)

they are tahor.

פרק ט משנה ב

A barrel

that is filled

with tahor beverages

and a [metal] straw is in it

sealed with a tightly fitting cover

and placed under a canopy with a corpse,

Beis Shammai say

the barrel and the beverage are tahor

and the straw is tamei,

and Beis Hillel say

the straw is also tahor;

Beis Hillel retracted

to rule according to the words of Beis Shammai.